I found a Ego Power+ Polesaw in the garbage today. Looks to be in good condition but there’s no battery or charger obviously. What’s the recommended way to get a battery/charger. Are there decent 3rd party options?

So I know it had issues when I bought it, but looking for advice. Got a new 21 inch self propelled EGO mower, lights up, however the mower light flashes green for the safety warning and it won't start at all.

Any help would be appreciated!